1. Field of Invention
This invention relates to coupling systems for transferring materials from one flow conduit to another.
2. Description of the Prior Art
Disposable medicament-containing cartridge-needle units for use in conjunction with reusable hypodermic syringe holders are well known in the art. Such cartridges conventionally feature a cylindrical body closed at the proximal end with a flexible piston slidable within the bore of the cartridge and closed at the distal necked-down end with a diaphragm secured to the cartridge by a crimped-on metal collar. The necked-down distal end conventionally is fitted with a steel needle/needle hub unit and a needle sheath. Such needle/needle hub units have, minimally, a sharp end, typical of the type associated with hypodermic syringes.
Such cartridge-needle units can be used in conjunction with reusable syringe holders which allow the user to avoid handling the cartridge-needle unit when the needle is exposed. Nevertheless, health care workers are especially susceptible to accidental and potentially infectious, and indeed, on occasion, possibly fatal, needle strikes due to the careless handling and/or disposing of the cartridge-needle unit after use. The consequences to health care workers of strikes from needles contaminated with various infectious diseases such as hepatitis or AIDS can be particularly severe. The frequency of such accidental needle strikes in the United States is surprisingly great, and has been estimated to be approximately one million needle strikes per year. Moreover, the cost to health care organizations for the testing of health care workers accidentally stricken by used needles is a significant burden on health care costs. Therefore, it would be desirable to further protect health care workers by providing medicament containing cartridges without having to expose the user to the needle commonly associated with such cartridges.
In response to the "accidental needle strike" situation, numerous devices have been developed which typically shield or cover the sharp needle tip. One recently developed system, as described in PCT/US89/00273, comprises a pre-slit injection site specifically designed to receive a blunt cannula. Commercially available under the InterLink trademark, this pre-slit injection site and blunt cannula have been adapted for intravenous administration as described in pending U.S. and foreign patent applications. One of the key features of this system is the elimination of traditional "sharp" needles which are used in numerous procedures. For example, as described in PCT/US90/01350, the blunt cannula device is depicted in a press-fit combination with a syringe of known construction. Rather than using a traditional needle, the blunt cannula device is attached to the syringe and then inserted through the pre-slit injection site located in an IV tubing line. The content of the syringe is then delivered into the IV line. Once the content is delivered, the cannula is withdrawn from the site and properly disposed. Hence, the administration of the syringe content, through an IV line, can now be completed without the use of a standard needle.
Hence, it would be highly desirable to provide conventional disposable medicament cartridges adaptable to such blunt cannulae and useable with such pre-slit injection sites.